Cure and thermal stability of an addition-cure-type thermoset PN-PAA

The miscibility of reactive blends of PN (Propargyl novolac) resin and PAA (Polyarylcetylene) resin was studied. Evaluation on the storage stability, processability of the blends and thermal stability of the cured blends were also presented. As evidenced from phase observation, DSC analysis, SEM and TEM investigation, PN-PAA reactive blends were completely homogeneous. Compared with PAA, the blends exhibited improved storage stability at room temperature. The blends could be cured in a controllable way, thus the processability of the blends was marginally improved compared with that of PAA resin. DMA and TGA analyses indicated that the blends possessed high thermal stability (glass transition temperature as high as 380°C). Owing to the low viscosity of the blends and a proper gel time, as well as the elimination of volatiles during the curing process, the reactive blends are suitable for many processes including RTM (Resin transfer mold) .The reactive blends of PN resin and PAA resin are amongst novel matrices of advanced materials for high temperature ablative and thermo-structural applications.